This invention relates generally to a machine for extracting substantially the whole tree from its position in the ground. More particularly, it relates to a device for shearing certain of the roots, grasping the stem and then extracting the stem/root combination while applying selected vibratory forces to the tree mass.
In the past, it has not been necessary to consider the desirability and/or economic factors in extracting wood fiber contained in the portion of a tree commonly referred to as the stump/root portion mainly because there was sufficient wood fiber available from the above-ground harvested stems. The traditional method of harvesting trees is to sever the stem at a point somewhere close to ground level and then leave the stump and root system in the ground. In view of the projected wood fiber demand over time, it has now become necessary to consider that wood fiber below ground level.
As is well understood by those familiar with commercially growing forests, a substantial portion of wood fiber is contained in the stump/root portion of the overall tree, and if an efficient economical way of extracting that wood fiber were available, then, additional wood fiber could be made available to satisfy projected demands. The normal use for the below-ground wood fiber, as one skilled in the art would expect, is for use in the pulping process to make paper products. Generally, the wood fiber in the stump/root portion is not suitable for making lumber products, or the like.
Of course, it will be recognized by those skilled in the art, that different tree species have different subsurface characteristics. For example, most of the southern Pine species growing in the mid-South and Southeastern states have a plurality of laterally extending roots, together with a downwardly extending tap root, commonly referred to as a "carrot root." It is the tap root that contains a substantial amount of wood fiber that could be utilized in the pulping process to make useful end products.
As will be appreciated, there are many parameters to consider in designing a suitable apparatus to remove the subsurface wood fiber. For example, shearing forces to cross-cut through lateral roots must be considered as well as depth of shearing action, extraction forces to remove the whole tree and severed root system, dirt contained on the root system, and the hole left by removing the root system. Other considerations are productivity, cost, ease of maintenance, and flexibility.
Of course, others have recognized the value of extracting the wood fiber contained in the tree at subsurface levels. Certain earlier approaches extracted the stump and root system left after cutting, while several newer approaches extract the tree together with a certain portion of the root system. One example of such a whole tree extraction device is that currently being offered by Rome Industries of Cedar Town, Ga. This particular device is generally described in a publication entitled "Canadian Pulp and Paper Industry," June, 1975. The particular design disclosed in the aforementioned publication does have the ability to extract whole trees from the ground, but does not offer the cleaning function integral with the extraction unit. Another example of a whole tree extraction device may be seen by referring to U.S. Pat. No. 3,914,883 which was issued to A. G. Bodine. The Bodine device does have provision for applying vibratory movements to an extractor unit but not in the same manner nor with the same structure as does the present device.
Accordingly, from the foregoing, one object of the present invention is to provide a whole tree extraction device having the capability of cleaning the root system.
Another object is to provide a whole tree extraction device wherein vibration is applied in order to enhance the shearing, cleaning, and extraction process.
Another object is to provide a design utilizing vibratory forces that will extract and clean relatively large trees.
These, and other objects will become apparent upon reading the following specification in conjunction with the attached drawing.